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Industrial silicon, also known as silicon metal and crystalline silicon, is silver-gray crystalline, hard and brittle, and is smelted by quartz stone which SiO₂ purity 98.5%min. and other materials.Silicon metal is extremely versatile, is a basic industrial raw materials, mainly used in the production of silicone, polysilicon, in aerospace, aviation, electronics, organic chemical, smelting, thermal insulation refractory and other industries and fields.